1. Field of the Invention
The present invention relates to a patch and a patch preparation each of which is used for the protection of a skin, the transdermal administration of a drug, and the like.
2. Description of the Related Art
Patches and patch preparations each of which is used by being attached to a skin for the purposes of, for example, protecting the skin, fixing various medical devices, and transdermally administering a drug are each requested to have the following characteristics. That is, each of the patches and patch preparations shows sufficient pressure-sensitive adhesiveness upon attachment to the skin, and can be released and removed without contaminating the surface of the skin (causing, for example, an adhesive residue or stickiness) after its use. In addition, it is desirable that each of the patches and patch preparations be lowly stimulant to the skin.
Japanese Laid-open Patent Publication No. Hei 4-150865 discloses a patch containing, in its pressure-sensitive adhesive layer, a cross-linked product of a copolymer of: a (meth)acrylic acid alkyl ester or a mixture of the ester and a (meth) acrylic acid alkoxyalkyl ester; and a monomer containing a carboxyl group and/or a hydroxyl group. However, reactivity between an active component such as a drug and a carboxyl group must be taken into consideration because the pressure-sensitive adhesive layer in the above-mentioned patch contains the copolymer having a carboxyl group.
In addition, Japanese Laid-open Patent Publication No. 2003-313122 discloses a patch using an acrylic pressure-sensitive adhesive obtained by polymerizing: (meth)acrylic acid alkyl esters; and monomers copolymerizable with the (meth) acrylic acid alkyl ester and free of a carboxyl group and a sulfo group. Further, the pressure-sensitive adhesive layer of the patch in the document contains an organic liquid component and can be cross-linked. The document describes that the above-mentioned patch shows a small stimulus to a skin and has a feeling of softness while having such a sufficient cohesive strength that no adhesive residue occurs at the time of its release. However, an additional improvement in adhesive property of the pressure-sensitive adhesive free of a carboxyl group and a sulfo group disclosed in Japanese Laid-open Patent Publication No. 2003-313122 has been desired because the patch may be released from the skin when the patch is attached to a skin surface for a long time period or attached to a skin surface that moves to a large extent.